This invention relates to devices and methods for protecting enclosures within buildings from airborne contaminants such as the highly toxic chemical agents sarin, soman, and VX, and the highly infectious biological agent anthrax.
The recent increase in terrorist activity throughout the world poses a serious threat to virtually every member of society. Although many terrorist activities utilize bombs or other explosive devices, there is an increasing concern that devices which release chemical or biological agents will become the weapons of choice for terrorists. Chemical or biological weapons are most destructive when deployed in highly populated areas such as cities. If such a device is activated or detonated near or within an enclosed area, such as an office or apartment building, a chemical or biological agent may rapidly affect many of the building""s occupants. The interior of a building can be a particularly dangerous environment in the event of a chemical or biological attack because the contamination may spread much more quickly than the occupants can be evacuated from the building. Furthermore, a building""s HVAC system may actually speed dispersion of the contaminant if the system fails to remove the contaminant, or if there is no other means of containment or decontamination within the building.
Currently, many residential, commercial, and government buildings have not implemented measures to quickly and effectively contain airborne chemical or biological agents should such agents be released into the environment. Therefore, there is a need for a portable, highly effective system which can be quickly installed within residential, commercial, or government buildings to protect the occupants from exposure to airborne highly toxic chemical agents or highly infectious biological agents following contamination of the environment with such agents.
A variety of devices for purifying the airflow into or out of an enclosure are available. U.S. Pat. No. 4,790,863 to Nobiraki et al. discloses a thin, lightweight fan module having one or more fans contained within a casing; a thin, lightweight air filter module, and a porous air flow moderator disposed between the fan module and the air filter module. U.S. Pat. No. 4,905,578 to Curtis et al. discloses an apparatus for ventilating controlled areas that includes a blower located in an enclosure. U.S. Pat. No. 5,462,484 to Jung et al. discloses a self-contained air cleaning system for use in clean rooms, as does U.S. Pat. No. 5,876,279 to Renz et al. However, the prior art does not provide for a portable kit which can be quickly assembled and installed in any room within a building, and which contains all of the items needed to effectively protect the occupants from exposure to dangerous biological or chemical agents.
Accordingly, these and other disadvantages of the prior art are overcome by the present invention which provides a low-cost, portable filtration system for supplying [expedient] collective protection to a single room inside a residential, commercial, or government building. In a preferred embodiment of the present invention the protective filtration system is intended for installation in an interior door or window and includes an air-impermeable panel, a filtration assembly mounted within the air-impermeable panel for removing highly toxic chemical agents or highly infectious biological agents, and an adjustable frame for supporting the air-impermeable panel and the filtration assembly. The filtration assembly of the present invention includes at least one filtration unit suitable for removing highly toxic chemical agents or highly infectious biological agents, and a blower mounted either upstream or downstream from the filtration unit for pulling air through the filtration unit and providing overpressure to the protected room. A preferred embodiment of the present invention further includes a pressure gauge for measuring the pressure differential across the impermeable panel after the system is installed, and a control module for controlling the variable speed of the blower. In a preferred embodiment, the individual components of this invention are disassembled and packaged as a kit which is portable, and which may be rapidly assembled and installed to protect a single room in the event of biological or chemical contamination of the interior or exterior of a building.
Therefore, an object of the present invention is to provide a low-cost, portable filtration system capable of supplying collective protection to a single room inside a building by (i) positively pressurizing the room to minimize air leakage pathways, and (ii) purifying the air that passes into the room by means of a filtration assembly.
A further object of the present invention is to provide a protective action alternative that offers higher protection than sheltering-in-place or recirculation filters, at a much lower cost and complexity than a military-grade collective protection system.
Another object of the present invention is to provide a portable kit, the components of which can be rapidly assembled and installed to supply clean, pressurized air to a room of small volumetric proportions and low infiltration.
Further objects, advantages, and novel aspects of this invention will become apparent from a consideration of the drawings and subsequent detailed description.
10 Protective Filtration System
12 Control Module
14 Pressure Gauge
16 Adjustable Frame
18 Impermeable Panel
19 Opening
20 Filtration Assembly
21 Support Panel
22 Blower
24 First Casing
26 First Filtration Unit
28 Second Filtration Unit
30 Second Casing
32 Sleeve
34 Carrying Case